In the end of the steam-pipe solder the union of the steam-tap. Next make the stand for the engine and boiler. Make it out of a piece of deal eighteen inches long, five inches wide, and half an inch thick. Screw the bed-plate of the engine on one end of it, so that the after end of the plate is flush with the stand. The wood must be cut away under the square holes, to let the cranks work in. Screw two strips of copper at the other end, for the turned-in feet of the boiler to slide under. Put them so that the end of the boiler will be about three and a half inches from the fore end of the bed-plate. Put the boiler in its place, and bend the steam-pipe so that the union can be screwed to the steam-tap and the exhaust-pipe so that the end of it is opposite the projecting pipe from the boiler, and connect these two ends with a piece of indiarubber tubing.
Fig. 24
The spirit-lamp must be in the shape of a closed box, made of sheet copper, four inches wide, eight inches long, and three quarters of an inch deep. In the top cut five holes, as in [Fig. 24], a quarter of an inch in diameter. In these holes solder five tubes half an inch long, and projecting from the top a quarter of an inch. These are for the wicks. At the front end of the top solder a screw filling-tap. At this end solder also a piece of small pipe four inches long. This is to be bent so that it will stand upright outside the end of the boiler, and is to act as a vent, to prevent the spirit being forced too freely up the wicks. Fill the wick-holes tightly with cotton. Now fill the lamp half full of spirit. Pour hot water into the boiler till it just flows out of the top gauge-tap. See that all the taps are turned off. Light the lamp and put it under the boiler, and while steam is getting up oil the engine well with sewing-machine oil. In a short time the steam ought to be up and the engine at work. Try the reversing-gear and see if it acts properly. The engine ought to work smoothly and without noise, and the frame ought not to jar.
We must now make the screw propeller. The boat, which I suppose already made, is to be five feet long, ten inches wide, and eight inches deep, without the keel, and hollowed out to about a quarter of an inch thick at the gunwales and three-quarters of an inch thick at the bottom, and must be rather flat-bottomed, as steamships are, so that the inside at the bottom is five inches wide.
Fig. 25
Put the engine and boiler in the boat so that the boiler is a little abaft the middle. Cut away the dead wood of the stern to make a hole four inches high and two inches wide, as in [Fig. 25]. Bore a hole from the hole in the dead wood right through into the interior of the boat, as shown by the dotted lines in [Fig. 25]. This hole is to be directed to the centre of the fly-wheel of the engine. The shaft is made out of the quarter-inch wire. Cut a square pin and shoulder three-eighths of an inch long and an eighth of an inch square at one end of the shaft. Cut a piece of the same wire three and a half inches long and drill a square hole in the middle, and rivet it on the end of the shaft crosswise. In the hole in the stern of the boat you must fix a tube and stuffing-box, which may be got—together with the screw, which is to be a three-fanned one, measuring three inches across the fans—with the other things, of Messrs. Theobald and Co., and similar houses.
Put the shaft in its place inside the boat, with the cross-piece resting across the pins in the fly-wheel, about half way. Mark the end of the shaft so that it will project an inch and three-quarters, and cut it off there. The bearing must now be made out of a strip of brass one-sixteenth of an inch thick, three quarters of an inch wide, and two inches longer than the width of the inside of the boat. In the middle of this bore a hole a quarter of an inch in diameter, and bend one inch of each end at right angles to the other part. In each bent piece drill two small holes, to screw them to the sides of the boat by. Slip a piece of tubing, one inch long and of a size to fit tightly on the shaft, close up against the cross-piece. Put the shaft through the bearing and stuffing-box tube, and put the cross-piece on the pins in the fly-wheel, and screw the bearing to the boat, so that it is close against the tube on the shaft. The screw has a screw-bolt like the fly-wheel to fix it to the shaft by. Drill a small hole in the shaft for it, and put the screw on the end of the shaft and fix it by tightening the screw.